HPF Stage 2.5 turbo E46 M3 versus tuned Porsche 997 Turbo roll on

Here is a roll on race at the air strip featuring an E46 M3 with an HPF (Horsepower Freaks) Stage 2.5 turbo kit putting out 700 wheel horsepower versus a 997 Twin Turbo that is modified and who owner is claiming puts out 685 horsepower at the wheels. The E46 M3 beats the 997TT down pretty easily so it leaves one wondering if the Porsche is really putting out the power the owner is claiming. In all fairness to the 997TT though the E46 does appear to get a sizable jump.

The Porsche owner states traction was poor but hey, he has all wheel drive. Modifications to the 997TT consist of a Protomotive E85 tune, modified VTG turbos, IPD plenum, 83 pound injectors, champion intercooler, headers, catless exhaust, GT3 throttle body, and an intake. Check out the videos below one from the perspective of the M3 and the other from the 997TT.

If the cars have the same initial velocity, and same acceleration, you can see that the car that has been accelerating longer will always have a faster velocity. If the velocities are different, that means the cars aren't going to stay the same distance apart.

People on the race track often have this problem, thinking a similarly fast car is pulling on them out of turns but slowing them down on the slow sections. If you count their separation in time instead of car lengths, you can usually see that they are actually driving at the same speed. Example: 1 second time difference at 100mph is going to be 147 feet, 1 second time difference going 50mph is going to be 73 feet apart.